The word "相互" is formed by combining the characters "相" and "互", both of which individually convey meanings related to mutuality and reciprocity. "相" often indicates mutual action or relationship, while "互" explicitly denotes reciprocal interaction. Together, they create a compound word that emphasizes mutual or reciprocal relations, such as in phrases like "相互帮助" (help each other), through the semantic reinforcement of their similar meanings.